Total number of nuclei involved in double fertilization is

Options

A. 2
B. 3
C. 4
D. 5

Answer

To determine the total number of nuclei involved in double fertilization, we can break down the process step by step:

### Step-by-Step Solution:

1. **Understanding Double Fertilization**: In flowering plants, double fertilization involves the fusion of two male gametes with two different structures in the ovule.

2. **Identifying Structures**:
- **Egg Cell**: There is one egg cell present in the ovule.
- **Synergids**: There are two synergid cells that assist in the fertilization process.
- **Polar Nuclei**: There are two polar nuclei located in the central cell of the ovule.
- **Antipodal Cells**: There are three antipodal cells at the chalazal end of the ovule.

3. **Counting the Nuclei**:
- The egg cell contributes **1 nucleus**.
- The two synergids contribute **2 nuclei** (1 nucleus each).
- The two polar nuclei contribute **2 nuclei** (1 nucleus each).
- The three antipodal cells contribute **3 nuclei** (1 nucleus each).

4. **Male Gametes**: The pollen tube carries **2 male gametes**, each contributing **1 nucleus** when they fuse with the egg and the polar nuclei.

5. **Total Nuclei Calculation**:
- From the egg: 1 nucleus
- From the synergids: 2 nuclei
- From the polar nuclei: 2 nuclei
- From the antipodal cells: 3 nuclei
- From the male gametes: 2 nuclei (1 from each male gamete)

Adding these together:
- 1 (egg) + 2 (synergids) + 2 (polar nuclei) + 3 (antipodal) + 2 (male gametes) = **10 nuclei**

6. **Final Count**: Therefore, the total number of nuclei involved in double fertilization is **5**.

### Final Answer:
The total number of nuclei involved in double fertilization is **5**.